Adjustable shoring member



Dec. 5, 1967 R. D. RAMBELLE ADJUSTABLE SHORING MEMBER 2 Sheets-Sheet 1Filed April 23, 1965 ('IIIIIIAII- z /l/l/l/q, 5/ .526 H6130 Dec. 5, 1967D. RAMBELLE ADJUSTABLE SHORING MEMBER 2 Sheets-Sheet 2 252i F/G. 7

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United States Patent 3,356,330 ADJUSTABLE SHORING MEMBER Robert D.Rambelle, 102-26 86th Ave., Richmond Hill, N.Y. 11418 Filed Apr. 23,1965, Ser. No. 450,308 6 Claims. (Cl. 248354) The present inventionrelates to an adjustable shoring member for use in providing temporarysupport of building forms and the like which has significant advantagesover shoring members heretofore utilized for this, purpose. The presentinvention may be used with particular economic and practical advantageduring the formation of concrete floors in multi-storied buildings wherethe elevation between floors remains constant throughout all or most ofthe building structure.

Concrete used in large structural construction is a heavy, semi-liquidmaterial, comprised of various proportions of sand, gravel, cement andwater, and requires a firm base on which to be poured, so that it canset and harden. In the formation of concrete slabs and floors, astructural framework comprised of horizontal joist members (also calledstringers) supported at spaced locations by vertical shoring members isemployed to provide temporary support for a plywood or other form uponwhich the concrete is poured. After the concrete is hardened, thejoists, shoring and plywood forms are then removed, as the concreteslab, which typically is reinforced with steel rods, has becomeself-supporting and capable of bearing substantial loads.

Conventional shoring members used to support the joist members arein theform either of heavy wooden posts cut to size, or adjustable steeljacks. In the latter type of shoring, which is typically comprised oftwo round tubular members telescoping one inside the other, the innermember of the jack is provided with pairs of diametricallyopposed holesspaced along its axis, and the upper portion of the outer member isprovided with a single pair of slots through which a fastener pin can beinserted. In addition, an internally-threaded circular sleeve element isprovided for engagement with a threaded portion on the outer tube memberof the jack.

During erection of the jack, the inner member is extended out to theapproximate height required, and a fastener pin is inserted through theslots in the outer member and into an aligned pair of holes in the innermember to lock the jack in this extended position. The jack is thenadjusted to the exact elevation required by rotation of the threadedsleeve element. Stripping of the jack involves the same operations, butin a reverse sequence.

It is readily apparent that the above-described method of erection andstripping, employed with jacks of conventional design, is bothbothersome and time consuming. The recurring operations of extension,fine adjustment, and lowering of the jack during stripping, which mustbe performed each time a concrete floor is poured, are expensive andrender the use of such jacks economically unfeasible for the high-rise,multi-storied structures which are being built today. Accordingly,wooden shoring members, custom-cut to the exact length required, are nowused almost exclusively instead of adjustable steel jacks in theconstruction of high-rise buildings. However, wooden shoring membersdeteriorate rapidly due to the combined effects of environment and wearand they therefore have but a limited number of reuses before they mustbe scrapped.

In contrast to these disadvantages and limitations possessed by shoringmembers heretofore known to the art, the present invention provides anadjustable shoring member which can be readily erected and stripped inbut a fraction of the time required with conventional steel jacks. Onceadjusted and set to the length required, the shore of the present designcan be readily stripped down by a special technique without thenecessity of lowering the member, and can be reerected for the formationof a subsequent stage of concrete flooring at the same elevation withoutany further adjustment in length being required.

In an exemplary embodiment of the invention, the shoring member is oflightweight metal construction and is comprised of two tubular elementsof generally square cross-section, one telescoping into the other. Aplurality of opposed sets of holes are incrementally spaced on the sidesand along the length of the inner tube element, and a set comprised ofat least a single pair of opposed holes are similarly provided in theouter tube element. The horizontal joist, which the shoring membersupports, rests on a head section of generally ll-shaped configurationwhich is connected to the body of the shore. A pivot pin, passingthrough the two side wings of the head section and the upper, extendedend of the outer tube element, permits rotation of the shore relative toits head section in a single direction.

With the above-described arrangement, the length of the shore, whenextended, can be adjusted to within a small increment of the requiredheight and then locked by the insertion of a fastener pin through thealigned holes of the overlapping portions of the outer and inner tubularelements. A fine adjustment in the effective height of the shoringmember is then accomplished by the insertion, between the bottom of thesupported joist and the base of the head section, of one or more thinsheets of plastic or metal which act as shims to incrementally raise thejoist to the final elevation required.

After formation of the slab structure, the shoring member of the presentinvention may be readily stripped by directing a hammer blow against thebody of the shore at a point near its bottom and parallel to the longaxis of the supported joist. The force of the hammer blow will cause thebody of the shore to rotate, like a hinge, about the pin which pivotallyconnects it to the H-shaped head section, and the shore will then fallout from beneath the propped joist as desired. As the shoring memberremains locked in the extended position, which roughly corresponds tothe elevation required for the supported joist, the shore can be readilyreerected to support a subsequent stage of floor construction Withoutany further gross adjustment being required.

To facilitate the stripping of the shoring member in the special mannerdescribed above, the extended, bottom end of the inner tubular elementis preferably terminated in a base plate of flat, rectangularconfiguration whose short dimension is smaller than the diagonal of theinner 1 tube and lies in the direction of the stripping action Ge,

parallel to the supported joist). As will be hereinafter explained, sucha base plate configuration minimizes the amount of force required in thehammer blow to knock the shore member from beneath its supported joist.

By reason of its simplified construction, and its ability to be readilystripped down without lowering its length, the novel shoring memberdesign of the present invention is exceedingly economical both in itsmanufacture and in its use. Particularly in the construction ofmultistoried, high-rise buildings, where the elevation between floors isgenerally invariant throughout the structure, the utilization of theshoring member disclosed herein is especially attractive in view of theconsiderable time and expense saved in the erection and stripping of thetemporary support forms used for the formation of the concrete slabs.

It is therefore a principal objective of the present invention toprovide a novel design for an adjustable shoring member, for use as atemporary support for building U forms and the like, which may bereadily stripped down without lowering the length of the shore.

It is a further objective of the present invention to provide a noveldesign for an adjustable shoring member, for use as a temporary supportin the formation of concrete slabs, which can be readily adjusted to adesired length, and then stripped down and re-erected without requiringany readjustment in length.

It is another objective of the present invention to provide anadjustable shoring beam of novel design which is especially advantageousfor use in forming the concrete floors and slabs of multi-storied,high-rise building structures.

It is still another objective of the present invention to provide in anadjustable shoring beam a means for providing a fine length adjustmentwhich comprises a plurality of thin insert shims of plastic or metal.

The foregoing and other objectives, features and advantages of thepresent invention will be more readily understood upon consideration ofthe following detailed description of the invention, taken inconjunction with the accompanying drawings.

FIG. 1 is a front elevational view of an illustrative embodiment of anadjustable shoring member constructed in accordance with the presentinvention.

FIG. 2 is a side elevational view of the shoring member shown in FIG. 1.

FIG. 3 is an enlarged side detail view, taken along the line 3-3 in FIG.1 and partially broken away, showing the head section of the shoringmember.

FIG. 3a is a cross-sectional view of one of the insert shims shown inFIG. 3.

FIG. 4 is a front view, partially broken away, of the head section shownin FIG. 3.

FIG. 5 is an enlarged plan view of the shoring member, taken along theline 55 in FIG. 1.

FIG. 6 is an enlarged sectional view of the shoring member, taken alongthe line 6-6 of FIG. 1, together with a vector diagram illustratingcertain force relationships present during the stripping operation.

FIG. 7 is an enlarged side detail view of a modification of the headsection of the shoring member shown in FIG. 1.

FIG. 7a is a cross-sectional view of one of the insert shims adapted foruse in the modified head section shown in FIG. 7.

FIG. 8 is a sectional view of the modified head section, taken along theline 8-8 in FIG. 7.

Referring now to FIGS. 1 and 2, there is shown an illustrativeembodiment of an adjustable shoring member, constructed in accordancewith the teachings of the present invention. The shore, designatedgenerally by 10, is shown in use supporting a wooden joist member 15,and is fabricated from a suitably strong and lightweight metal, such asaluminum.

In this exemplary embodiment, the shore 10 is comprised of three majorparts; an inner tubular element 20, an outer tubular element 30, and apivotable head section 40. The two tubular elements are of substantiallysquare, hollow cross-section, with the inner tube telescoping into theouter tube 30. A plurality of holes are arranged by pairs in twostaggered sets 23 and 24 on opposing sides of the inner tube 20, withthe holes in each set being incrementally spaced, typically about 2"apart, along the length of the inner tube element. Two pairs of holes32, similarly located on opposing sides, are provided near the lower endof the outer tube element 30.

With the shore adjusted to the approximate height desired for thesupported joist, a fastener pin 25 is passed through the aligned holesof the overlapping portions of the outer and inner tubular elements 20,to lock the shore in the extended position. As contrasted with the useof round tubular elements, the square shape of the tubes 20 and 30prevents rotary displacement of one relative to the other, and thusfacilitates alignment of the holes in the inner and outer tube membersfor insertion of the fastener pin.

As best shown in FIGS. 3 and 4, the upper end of the shore is terminatedin a head section 40, which, in a preferred embodiment, is of generally[fl-shaped configuration having a horizontal base portion 41 and a pairof downwardly projecting side wings 45. This head section 40 ispivotally secured by a pin 35 passing through the side wings 45 and theupper end of the outer tube element 30. Sufiicient clearance between thebase 41 of the head section and the terminal end of the outer tube 30 isprovided to permit the Fl-shaped head portion to be freely rotatable inan are about the pivot pin 35.

In use, the shore is erected with the head section 40 positioned asshown, that is, with the pivot axis (pin 35) perpendicular to the longaxis of the supported joist 15, so that the shore head 40 is freelytiltable only in a plane parallel to the joist. It should be noted,however, that this pivoting-head construction of the shore member doesnot adversely affect the stability of the support structure againsttipping since, when fully erected, the joist member 15 will pass overthe heads of several such shores. Furthermore, the pin connection of thehead section 40 to the body of the shore 10 ensures that the shoremember will be subjected to concentric loading conditions under theweight of the joist 15, as the head section will tilt as needed tofollow the deflection of the joist under load, thus preventing theestablishment of undesirable bending moments in the shore.

After the shore has been adjusted to within a small increment of therequired height, by the insertion of the fastener pin 25, a fineadjustment is then accomplished by the insertion, between the joistmember 15 and the base 41 of the shore head section, of a number, asneeded, of thin shims 50 comprised of plastic or metal material. Theseinsert shims 50, the details of which are best shown in FIG. 3a, areexemplarily of A" thickness and are provided on one side with a pair ofprojecting ridges 52b, and on the other side with mating keyway grooves52a. The base 41 of the shore head section 40 is similarly provided witha pair of keyway grooves 41a. This arrangement permits a large number ofthe shims to be vertically stacked in an interlocked fashion on top ofthe shore head section.

If desired, a marker pin 17 may be located at predetermined intervalsalong the bottom of the joist member 15 to facilitate the spacing of thevertical shores. In such an arrangement a central opening 42 in the baseof the shore head section 40, as well as corresponding holes 51 in theinsert shims 50, are then provided to accommodate the marker pin 17.

In a preferred embodiment, the shore 10 is supported upon a fiat baseplate 26 rigidly secured to the lower end of the inner tubular element20. As is best shown in FIG. 6, the base plate 26 is of rectangularconfiguration and is arranged so that its long dimension, indicated by26l, is perpendicular to the axis of the supported joist (i.e., parallelto the pivot pin 35), and its short dimension, indicated by 26w, issmaller than the diagonal length of the shores inner tube element 20, inorder to facilitate the stripping operation hereafter described.

After the overlying concrete construction has hardened and it is desiredto remove the building forms and the supporting framework, the shore 10may be readily stripped by directing a hammer blow, as indicated by thearrow F in FIG. 1, at a point near its bottom and parallel to the longaxis of the support joist 15. This blow will cause the body of the shoreto rotate about the pivot pin 35 along a circular arc whose radius isrepresented by the arrow S.

By having the size of the base plate 26 in the direction of thestripping action of small dimension, the amount of force required in thehammer blow to knock out the shore 10 from beneath the joist 15 isminimized. If this width dimension of the base plate were made too great(for example, considerably larger than the cross-sectional size of theshore body), then it would be quite difficult to strip the shore in themanner described above. Correspondingly, it is not practical to reducethe width dimension of the base plate 26 to a relative size much smallerthan that shown, because of excessive bearing stresses which would thenbe produced in the concrete foundation on which the shore rests.

The force-vector diagram shown in FIG. 6 illustrates a further importantadvantage of the square tube design utilized in the shore member of thepresent invention. In stripping, the hammer blow F, directed against thecorner of the inner tube element 20 of the short body, generates areaction force R in opposition thereto which can be resolved into twocomponents R and R With the use of square sections for the shores innerand outer tubular elements 20 and 30, these component forces R and Rwhich are aligned along the walls of the tube section, are equalized inmagnitude. Accordingly, there is no tendency during the stripping actionfor the shore body to rotate in a direction other than parallel to theaxis of the joist 15. This minimizes the amount of force required tostrip the shore, since all of the force of the hammer blow istransferred into a moment-arm producing rotation of the shore body aboutthe pivot pin 35", and no energy is dissipated in directions in whichmovement is restrained.

FIGS. 7, 7a, and 8 are directed to a modification of the head section ofthe shore embodiment which is described in the present invention. Inthis modification, the l-shaped head section 60, similar to thepreferred embodiment shown in FIGS. 3 and 4, has a base portion 61 and apair of side wings 65 pivotally connected by a pin 35 to the upper end30 of the shore body. However, in this variation, the head section 60also includes a pair of upwardly projecting flanges 66 and 67 whoseinterior surfaces are provided with grooves 68 to slidably receive andretain a plurality of thin insert shims 70 of the modified design shownin FIG. 7a. In this modified shim design, which is somewhat moresimplified than that of the embodiment shown in FIG. 3a, theinterlocking arrangement of ridges and keyways have been eliminatedsince the lateral support provided by the walls of the head flanges 66and 67 are sufficient to retain the shims in position.

In order to accommodate the marker pin 17 projecting from the bottom ofthe supported joist 15, both the base of the shore head section 60, aswell as the insert shims 70, are provided with central openings 62 and71, respectively. If desired, the modified head design shown in FIGS. 7and 8 may also include means, such as tacks 69 passing through openings72 in the longer one of its two flange portions, for fastening the headsection 60 to the body of the joist 15. Such an arrangement provides afirmer support base for the pivot axis provided by the pin 35 during thestripping operation, and thus further facilitates the removal of theshore by the simplified manner hereinbefore described.

The terms and expressions which have been employed here are used asterms of description and not of limitation, and there is no intention,in the use of such terms and expressions, of excluding equivalents ofthe features shown and described, or portions thereof, it beingrecognized that various modifications are possible within the scope ofthe invention claimed.

What is claimed is:

1. A rapidly-strippable shoring member, for use in providing temporaryvertical support of building forms and the like, comprising (a) avertically-positioned columnar member,

(b) a head element having a horizontal base surface for contacting theundersurface of a building form,

(c) means for pivotally connecting said head element to the upperextremity of said columnar member in a manner permitting said headelement to be rotatable in a vertical plane relative to said-member, and

(d) a flat, substantially rectangular base plate. rigidly secured to thelower extremity of said columnar 5 member, said base plate having itslong dimension arranged parallel to the axis of rotation of said headelement, and its short dimension being smaller than the thickness ofsaid member in order to facilitate stripping of said shore by theapplication of an impulse force against said vertically-positionedcolumnar member in a horizontal direction substantially perpendicular tosaid axis of rotation of said a head element.

2. A rapidly-strippable shoring member, for use in providing temporaryvertical support of building forms and the like, comprising (a) avertically-positioned shore body of adjustable length, 7 j

(b) fastening means for locking said shore body in an extended position,

(c) a head element of generally H-shaped configuration with a horizontalcenter section and two downwardly-projecting side wings spaced apart bythe thickness of said shore body.

(d) means for pivotally connecting the two side wings of said headelement to the upper extremity of said shore body interposedtherebetween, in a manner permitting said head element to be rotatablein a vertical plane relative to said vertically-positioned shore body,and

(e) a fiat, substantially rectangular base plate rigidly secured to thelower extremity of said shore body, said base plate having its longdimension arranged parallel to the axis of rotation of said headelement,

and its short dimension being smaller than the thick- 3. An adjustableshoring member, for use in providing temporary vertical support ofbuilding forms and the like,

comprising (a) a sh-ore body having an inner tubular element telescopinginto an outer tubular element,

(b) means for grossly adjusting said shore to a predetermined height bylocking said inner tubular element to said outer tubular element in anextended vertical position,

(c) a head element secured to the upper extremity of saidvertically-positioned shore body and having a horizontal base surfaceadapted for contacting the undersurface of a building form,

(d) means for finely adjusting said shore to said predetermined heightcomprising a plurality of thin shims adapted to be inserted, as needed,between said base surface of said shore head element and saidundersurface of said building form, and

(e) slida'bly-engaging means formed by mating portions on said shims andsaid head element for securing said shims to said head element instacked form.

4. An adjustable, rapidly-strippable shoring member,

65 for use in providing temporary vertical support of building forms andthe like, comprising (a) a shore body having an inner tubular elementtelescoping into an outer tubular element,

70 (b) means for grossly adjusting said shore to a predetermined heightby locking said inner tubular element to said outer tubular element inan extended position,

(c) a head element of generally Fl-shaped configuration with ahorizontal center section and two downwardly projecting side wingsspaced apart by the thickness of said shore body,

(d) means for pivotally connecting the two side wings of said headelement to the upper extremity of said shore body interposedthere'between, in a manner permitting said head element to be rotatablein a vertical plane relative to said vertically-positioned shore body,

(e) means for finely adjusting said shore to said predetermined heightcomprising a plurality of thin shims adapted to be inserted, as needed,between the upper surface of the center section of said head element andthe undersurface of a building form, together with means formed bymating portions on said shims and head element for slidably engaging andsecuring said shims in stacked form to said head element, and

(f) a fiat, substantially rectangular base plate rigidly secured to thelower extremity of said verticallypositioned shore body, said base platehaving its long dimension arranged parallel to the axis of rotation ofsaid head element, and its short dimension being smaller than thethickness of said shore body in order to facilitate stripping of saidshore by the application of an impulse force against saidverticallypositioned shore body in a horizontal direction substantiallyperpendicular to said axis of rotation of said head element, saidstripping action being effected without requiring either removal of saidstacked shims from said head element or retraction of said shoringmember from said extended position.

5. T he adjustable shoring member set forth in claim 4 characterized inthat said gross-adjustment means is comprised of a plurality of opposedsets of holes incrementally 8 spaced on the sides and along the lengthof one of said tubular elements of said shore body, at least a singlepair of opposed holes similarly provided in the other of said tubularelements, and a fastener pin passed through the aligned holes of theoverlapping portions of said telescoping outer and inner tubularelements.

6. Means for finely adjusting a shoring member to a predetermined heightcomprising, a shore, a plurality of thin extension shims adapted to beinserted, as needed, between an end of said shore and a support surface,and first means on the end of said shore mating with second means onsaid shims, said first and second means connecting by slidableengagement to secure said shims in stacked form on said shore end.

References Cited UNITED STATES PATENTS 1,832,782 11/1931 Leupen 248-3542,331,247 10/1943 Symons 248-357 2,504,291 4/ 1950 Alderfer 2483 542,532,168 11/1950 Jakoubek 248-354 2,684,222 7/1954 Miller 248-354 X3,043,549 7/ 1962 Wilkinson 248-451 FOREIGN PATENTS 1,330,262 5/1962France.

816,548 7/1959 Great Britain.

854,978 11/1960 Great Britain.

ROY D. FRAZIER, Primary Examiner.

CLAUDE A. LE ROY, Examiner.

W. D. LOULAN, Assistant Examiner.

1. A RAPIDLY-STRIPPABLE SHORING MEMBER, FOR USE IN PROVIDING TEMPORARY VERTICAL SUPPORT OF BUILDING FORMS AND THE LIKE, COMPRISING (A) A VERTICALLY-POSITIONED COLUMNAR MEMBER, (B) A HEAD ELEMENT HAVING A HORIZONTAL BASE SURFACE FOR CONTACTING THE UNDERSURFACE OF A BUILDING FORM, (C) MEANS FOR PIVOTALLY CONNECTNG SAID HEAD ELEMENT TO THE UPPER EXTREMITY OF SAID COLUMNAR MEMBER IN A MANNER PERMITTING SAID HEAD ELEMENT TO BE ROTATABLE IN A VERTICAL PLANE RELATIVE TO SAID MEMBER, AND (D) A FLAT, SUBSTANTIALLY RECTANGULAR BASE PLATE RIGIDLY SECURED TO THE LOWER EXTREMITY OF SAID COLUMNAR MEMBER, SAID BASE PLATE HAVING ITS LONG DIMENSION ARRANGED PARALLEL TO THE AXIS OF ROTATION OF SAID HEAD ELEMENT, AND ITS SHORT DIMENSION BEING SMALLER THAN THE THICKNESS OF SAID MEMBER IN ORDER TO FACILITATE STRIPPING OF SAID SHORE BY THE APPLICATION OF AN IMPULSE FORCE AGAINST SAID VERTICALLY-POSITIONED CO- 